In recent years pads of paper have become very popular in which each sheet has a marginal stub area bearing on its underside a band of non-drying, slightly-tacky adhesive which, while permanently bonded to the underside of the sheet, only temporarily bonds to other surfaces, including to the stub areas of the top surfaces of respectively adjacent like sheets in the stack which constitutes the pad.
The general concept of such a product is disclosed in the Swiss patent of Eugster 452,479, dated May 31, 1986.
Eugster discloses a paper pad that is composed of self-adhesive individual sheets and is characterised in that each sheet is detachably joined to the sheet underneath it by means of a non-drying adhesive and in that the strip of adhesive provided at the edge of each individual sheet has one side which is smooth and adherent but does not take up adhesive while the other side carries the adhesive. The side carrying the adhesive may be arranged on the underside of the sheet. The adhesive applied to this side cannot be removed without chemical agents. When two such surfaces of adhesive strip which have been glued together are separated, virtually all the adhesive is left on the underside while the upper surface remains unwetted.
When assembling such a pad with the aid of non-drying adhesive, the top edge of each individual sheet is mechanically pressed with its underside, which receives adhesives, to the smooth upper surface of the other sheet, which does not take up adhesive. The individual sheets are thereby bonded together but they are not permanently fixed together, that is to say they are not glued together but can be separated one by one by hand. When a sheet is removed, the adhesive is left on the underside of the sheet so that the sheet which has been removed can be fixed by light finger pressure to another surface without the use of fresh adhesive.
Adhesives and paper useful in making such products are well known in the particular art.
When such pads first became widely available to the public in the United States about 10 years ago, the individual sheets bore no preprinting whatsoever, and the major uses were for temporarily tabbing pages of interest on documents, sometimes with notations field-applied, e.g. for indicating where a typographical correction to the adjacent text was needed, and for leaving notes in conspicuous places, e.g. on or about a person's desk, by their telephone, on a book or correspondance, on their refrigerator door and so forth. After a matter of time, a few months or perhaps a couple of years or so, pads of such sheets, containing identical designs, preprinted information or a format or gridwork for information on each sheet made their appearance. One example is a preprinted gridwork for leaving a message that one person would like to contact, or is attempting to contact another person by telephone or in some other way. Another is a pad of preprinted routing slips for books, correspondance or documents. Pads of humorous one-sheet greeting cards preprinted and assembled in a like matter even more recently have become available. However, in each instance of which the present inventor is aware, all sheets in any one stack have been preprinted with the identical information and/or decoration.
The present inventor is an employee of a company which not only makes and sells, under the trademark Note-Stix, several varieties of note pads of the type which has just been described, but also has a regular business of making and selling a wide variety of business forms, including ones which are available in pad form, and ones which are furnished in sets, each set being made up of a stack of several sheets or "parts" which are serially attached to one another along at least one edge or margin of each sheet. Frequently, each part in a set is different from the others in some readily apparent way, e.g. it is in a different color and bears an indication that it is to be retained by or routed to a particular party, office or functional unit. It is not uncommmon for sheets in such sets to be interleaved with or to bear as coatings on their undersides pressure-activated copy-making material such as carbon paper or carbonless coatings of micro-encapsulated ink. In some cases the set has a definite marginal strip or stub composed in part of a portion of each of the form parts, from which the remainder of at least one of the sheets can be detached, e.g. along a line of weakness such as a line of pre-formed perforation, leaving behind the stub or marginal strip, and often one or more of the form parts.
However, to the present inventor's knowledge there has been heretofore little or no effective cross-fertilization of these two fields of technology, i.e. pads of temporarily adhered notes, and sets of multiple-part forms. The present invention involves an advantageous hybridization of these two fields of technology.